The present invention concerns a drive mechanism unit for moving a cover in an motor vehicle. The cover may be rigid, folded or, for a covering blind, rolled to be extendable or retractable.
A cover serves to block the view into the trunk. The cover additionally has a safety function since the cover may retain objects in the trunk in case of an accident.
A covering blind known per se substantially consists of a winding shaft and a cover which can be wound onto the winding shaft by means of a spring means. The cover can be extended or retracted to cover parts of a trunk, loading space or other regions of a motor vehicle.
A station wagon has no permanent, stationarily mounted rigid cover or limit of the trunk such that the trunk can have a variable design and permit optimum loading of the vehicle.
In a similar fashion, covers are used also for coupe convertible cars with foldable metal roof. The vehicle roof which consists of several parts in these vehicles, can be automatically folded and stored in the trunk. A cover which subdivides the trunk must be drawn out before opening the vehicle roof. The drawn-out cover marks the available useful space of the trunk so that the user does not put any luggage in the region of the trunk which is required later by the folded vehicle roof. It shall be prevented that the vehicle roof squashes the luggage when the roof is introduced into the trunk or that the mechanism for moving the vehicle roof is damaged. The extended state of the cover can be monitored with an electric contact or a sensor to start motor-driven opening of the roof only when the cover has been extended.
Covers are also used as sun protection on the windows of the vehicle. The cover must be extended and retracted also in this case.
For this reason, the invention can be used anywhere in the vehicle where defined movement of a cover is required.
Manually operable covering blinds are known from practice for station wagons. A motor driven cover is disclosed e.g. in DE 195 39 848 A1.
The realization of electromotive drive mechanisms for covers in a vehicle poses in general the following technical problems: The space required for installation shall be as small as possible. The drive must be designed such that the cover is uniformly moved or extended or retracted. Mounting shall be quick and simple.
These problems are solved by a drive mechanism unit in accordance with claim 1 comprising a drive motor, preferably an electromotor, for driving a flexible shaft and a gearing for converting rotation of the shaft into a translation of a drive element connected with a carrier, wherein the carrier is provided for deflecting the cover.
In a preferred realization of the gearing, the gearing comprises a driven gear wheel for engagement in an outer profile of the flexible shaft.
The drive elements for moving the carrier may have different designs. The drive elements for reciprocating motion of the carrier may be formed by a flexible shaft whose surface has a profile into which the toothing of the driven gear wheel engages. On the other hand, the drive elements may be formed for deflecting the carrier through a deflected toothed belt which can be driven via the driven gear wheel. It is also feasible that the drive element is designed for reciprocating motion of the carrier through cable control or tension which can be wound via the driven gear wheel and is connected with the cover via the carrier.
A return spring may be provided whose spring force counteracts the winding process of the cable tension. The cover is automatically withdrawn into its initial position when the cable tension decreases. The return spring can be designed as tension or pressure spring depending on the arrangement of the cable control.
In accordance with the invention, the carrier is always connected to the drive element such that the carrier is displaced through actuation of the drive element. The carrier can be designed in different alternative shapes, i.e. as step, hook, slider, stop etc.
A preferred application of the drive mechanism unit for moving the cover in a motor vehicle, e.g. in a station wagon, is produced in that the electromotor for driving the flexible shaft is installed on the vehicle roof or vehicle inside roof and one drive element, one carrier and one gearing are each installed on or in the D-column of the vehicle wherein the gearing is provided for converting rotation of the shaft into a translation of a drive element for deflecting the carrier which engages on one end of the cover.